It takes deputies an average of 4.8 minutes to respond to calls in contract cities and 5.8 minutes in unincorporated areas. Officials attribute the difference to geography and poor roads.

It took Los Angeles County sheriff's deputies a minute longer to respond to emergency calls from unincorporated parts of the county than from cities that contract with the department for police services, according to a county audit.

The finding comes days after Supervisor Gloria Molina accused Sheriff Lee Baca of "stealing" police resources from residents in unincorporated neighborhoods and threatened to hire "independent private patrol cars" to backfill cuts in sheriff's patrols. She has accused Baca of providing better service to contract cities than to unincorporated areas.

According to the audit, which examined the last fiscal year, it took deputies, on average, 4.8 minutes to respond to emergency calls in contract cities compared with 5.8 minutes in unincorporated areas.

Sheriff's officials said the extra minute was because neighborhoods in unincorporated areas are more spread out and have more difficult road conditions.

The audit also found that Baca provided 91% of promised patrol hours to unincorporated areas, compared with 99% for cities and agencies that buy his services. Sheriff's officials blamed the difference on deep budget cuts imposed by the board that caused the department to leave dozens of deputy positions unfilled.

Adjusted for those cuts, the department was much closer to its goal — averaging 98.5% fulfillment of its pledged patrol hours, according to the audit.

The findings by the county's auditor-controller are expected to add more fuel to the ongoing debate between the sheriff and the board about whether the sheriff is shortchanging county residents who live outside city borders.

Baca and his predecessors have long wrangled with supervisors over funding and patrol resources.

Although the board sets the sheriff's budget, Baca, an elected official, has wide discretion on how to spend it. The Sheriff's Department polices about three-fourths of the county. Along with the unincorporated areas, Baca's deputies patrol more than 40 cities within the county that don't have their own police forces. The patrol obligations for those cities are set in contracts with the department, so county budget cuts are more likely to affect unincorporated areas.

On Tuesday, the board is expected to discuss Molina's idea to empower unincorporated neighborhoods to negotiate police contracts with the Sheriff's Department or some other agency — the same way incorporated cities do.

According to the audit, it costs the sheriff about $552 million to provide police services for contract cities and agencies, but the department gets approximately $371 million back. The auditor-controller suggested pursuing changes in state law or board policy to allow the sheriff to recoup more.

State law prohibits sheriffs from billing contract cities for non-patrol services provided countywide. So the department has provided a broad range of services — such as homicide and narcotics detectives, bomb squads and the county crime lab — at no extra charge.

Sheriff's spokesman Steve Whitmore said those rigid agreements — with contract cities, the county's courts, community colleges and public transit lines — limited where the sheriff could slash in the face of county budget woes.

The board has cut the sheriff's budget — now at $2.8 billion — by $128 million in 2010, $96 million in 2011 and $140 million last year, according to Whitmore.

The sheriff has already reassigned about two dozen gang enforcement deputies to patrol in unincorporated areas and has identified more than 90 other deputies to do the same, Whitmore said.

Molina's spokeswoman declined to suggest other areas where sheriff's officials should slash in light of funding cuts from the board but said that services to unincorporated areas should not be one of them.